I'm looking for just opinions here because there may not be an exact answer.


I often use existing 3-views to start my designs.
To do so, I turn a pdf into a tiff and then import that into my CAD program (Rhino, using the "PictureFrame" command).


So then I have the image to trace in my CAD file.
However, the lines of the image have a width.


So my question is for those who follow this path: What part of the image line do you use to trace?
Do you use the outer edge of the line?
The middle of the line?


Does it matter at all since you can Scale the finished drawing to whatever size you want?

With this sort of thing you need to decide Inner,Mid, or Outer of the line and stick to it l the way thought the project. Normally for me it outer seams to work well. and i think its the easiest,

For Me its scanning / Tracing images into Vectors parts for laser cutting,

Im an outside line person

What are you making ?

For me I see it like measuring the centerline distance between 2 bolts....left side of one bolt to the left side of the next equals an accurate center to center distance...like Hodge said ..pick a side and stick with it...hope it helps